There are numerous situations for which both pressurized oxygen and pressurized nitrogen are required. Since equipment cost and power cost are the important aspects of the cost of production, an objective of the present invention is to reduce the equipment or power cost, or both, for a process to produce both pressurized oxygen and nitrogen products.
U.S. Pat. No. 5,148,680 discloses a pumped liquid oxygen (LOX), pumped liquid nitrogen (LIN) process which produces both oxygen and nitrogen products at elevated pressure directly from the cold box by first boosting the pressure of liquid oxygen and liquid nitrogen to higher pressures and warming them by heat exchange with a portion of the feed air thereby at least partially condensing the portion. A portion of the condensed nitrogen from the top of the high pressure column is fed to the low pressure column as reflux.